Parameter Estimation in Type 2 Diabetes in the Presence of Unannounced Meals and Unmodelled Disturbances

A least squares strategy to estimate states and parameters for type 2 diabetes (T2D) patients based only on continuous glucose measurements and injected insulin in the presence of unannounced meals and disturbances, e.g., physical activity and stress, is presented. The strategy is based on a simple T2D patient model and tested with clinical data in addition to simulated data generated by using jump diffusion models for meals and disturbances. Three parameters are estimated together with the states, meals, and disturbances. The estimated meal states were shown to follow the trend of the unannounced meals. The strategy can be used to obtain a model with the estimated parameters for predictive control design. In addition, the strategy can also be used to test different insulin and meal plans with the estimated disturbances and parameters. Moreover, the paper demonstrates the ability of jump diffusion models to simulate meals and disturbances.